15 mile long run.

This morning I headed out early for my 15 mile long run.  Things were fine as I moved along at a steady pace for the first 10-11 miles.  I made a concerted effort to not go out too fast in the beginning so as to avoid the pitfalls I encountered on my 18 miler last week, and it seemed to work.  Unfortunately, at around mile 11 I started to get that pain in my knee again like I had last week.  It starts as an ache along the side of my knee, then all of a sudden my knee would spasm and just give out and I would have to start walking.  For the last 4 miles I took regular walking breaks every time the pain would flare up, then run as much as I could in between.  So, this long run went a lot better than the last one, but I still wish I could get my body whipped into shape so I could just enjoy it more.  I hate having to stop because my body isn't cooperating.  I finished the 15 miles in about 3 hours, so that worked out to an average pace of around 12:28 min/mile, which is about a minute per mile slower than I'd like to be for the marathon.  I've got a lot of work to do.